Hybrid surface from self-assembled layer and its effect on protein adsorption

We synthesized hybrid self-assembled monolayer (SAM) with short chain hydrophobic and hydrophilic groups on the same molecule. The physical characteristics such as surface roughness and surface energy of the synthesized hybrid SAM were compared with mono SAMs of amine, octyl and mixed amine-octyl SAM. We also compared the response of the surfaces towards adsorption of bovine serum albumin (BSA) using quartz crystal microbalance (QCM). We determined adsorbed amount (Γ) of BSA on the various surfaces from its various bulk concentrations. It follows the Langmuir adsorption isotherm in the concentration range of our study. The strength of adsorbed protein was characterized from the dissipation factor (ΔD). The highest ΔD value of adsorbed BSA was observed for the adsorption on hybrid surface. The arrangement of BSA on hybrid surface such that it leaded to soft layer, corresponded to the highest ΔD value. These findings suggest that the hybrid surface is a potential surface modifying agent of biomaterials.